程序代码：

#include <stdio.h>
#define add(y, n, L) ((y) + (n) > (L) ? ((y) + (n)) - (L) : (y) + (n))
#define sub(x, m, L) ((x) - (m) < (1) ? ((x) - (m)) + (L) : (x) - (m))

int main(void) {
    int x, y, m, n, L, t, kx, ky;

    scanf("%d%d%d%d%d", &x, &y, &m, &n, &L);
    if(x == y || !x || !y)
        return 0;
    for(t = 0, kx = x, ky = y; kx != ky ; t++) {
        kx = sub(kx, m, L + 1);
        ky = add(ky, n, L + 1);
    }

    printf("%d %d\n", t, kx); // printf("%d %d\n", t, ky);
    return 0;
}

程序代码：

#include <stdio.h>

int main(void) {
    int x, y, m, n, L, t, kx, ky;

    scanf("%d%d%d%d%d", &x, &y, &m, &n, &L);
    if(x == y || x < 1 || y < 1 || x > L + 1 || y > L + 1)
        return 0;
    for(t = 0, kx = x, ky = y; kx != ky ; t++) {
        kx = kx - m < 1 ? kx - m + (L + 1) : kx - m;
        ky = (ky + n) % (L + 1);
        printf("%d %d\n", kx, ky);
    }

    printf("%d %d\n", t, kx); // printf("%d %d\n", t, ky);
    return 0;
}

程序代码：

#include <stdio.h>

int main(int argc, char* argv[]) {
    int x, y, m, n, l;
    int a, b, k, t;
    
    while (scanf("%d %d %d %d %d", &x, &y, &m, &n, &l) == 5) {
        l++;
        m = l - m;
        a = x - y;
        b = m - n;
    
        if (b < 0) {
            a = -a;
            b = -b;
        }

        if (b == 0) {
            printf("Impossible\n");
            continue;
        }
        
        for (k = (a > 0 ? 1 : 0), t = (k * l - a) % b; t != 0 && k <= b; k++, t = (t + l % b) % b);    // 这个循环什么情况下会死循环？

        if (t == 0) {
            t = (k * l - a) / b;
            printf("%d %d\n", t, (t * m + x) % l);
        } else {
            printf("Impossible\n");
        }
    }
    return 0;
}

程序代码：

#include <stdio.h>

int main(int argc, char* argv[]) {
    int _x, _y, x, y, m, n, l, t;
    
    scanf("%d %d %d %d %d", &_x, &_y, &m, &n, &l);
    l++;
    m = l - m;
    x = (_x + m) % l;
    y = (_y + n) % l;
    for (t = 1; x != y && (x != _x || y != _y); t++) {
        x = (x + m) % l;
        y = (y + n) % l;
    }
    
    if (x == y) {
        printf("%d %d", t, x);
    } else {
        printf("Impossible");
    }
        
    return 0;
}